Abstract: A monitor terminal transmits a monitor request command to monitor a repeater station designated by an operator to a monitor server via the Internet. The monitor server detects a monitor station located in the communication range of the designated repeater station from the content of the received monitor request command, and transmits a monitor instruction command to the detected monitor station via the Internet. The monitor station intercepts a radio signal during transmission from the repeater station to a radio communication device or vice versa. Upon reception of the monitor instruction command, the monitor station transmits the intercepted radio signal as monitor data to the monitor server. The monitor server transfers the monitor data to the monitor terminal. Upon reception of the monitor data transferred from the monitor server, the monitor terminal radio-transmits the received monitor data using a radio wave format receivable by the radio communication device.

Abstract: A monitor terminal transmits a monitor request command to monitor a repeater station designated by an operator to a monitor server via the Internet. The monitor server detects a monitor station located in the communication range of the designated repeater station from the content of the received monitor request command, and transmits a monitor instruction command to the detected monitor station via the Internet. The monitor station intercepts a radio signal during transmission from the repeater station to a radio communication device or vice versa. Upon reception of the monitor instruction command, the monitor station transmits the intercepted radio signal as monitor data to the monitor server. The monitor server transfers the monitor data to the monitor terminal. Upon reception of the monitor data transferred from the monitor server, the monitor terminal radio-transmits the received monitor data using a radio wave format receivable by the radio communication device.

Abstract: An FM modulation signal is mixed with a pair of first local oscillation signals to be converted to a pair of base band signals. The base band signals are respectively mixed a pair of second local oscillation signals. The resultant signals are added together, thereby yielding an IF signal which is in turn detected. The local oscillator generates a reference oscillation signal whose frequency corresponds to a carrier component of the IF signal and frequency-divides the reference oscillation signal, thus generating the second local oscillation signals. The frequency of the first local oscillation signal converges to the one that has a given ratio to the frequency of the reference oscillation signal.

Abstract: In a radio communication system, a radio terminal for communicating with a plurality of radio terminals via repeaters is allowed simplified inputting of identification information of other radio terminals. The radio terminal used in the communication system in which communication is performed between a plurality of radio terminals via repeaters is structured as follows. The radio terminal has a receiving unit and controller for receiving identification information included in a signal sent by other radio terminals, a RAM for storing the signal received by the receiving unit and controller as received data, and a monitor for displaying various data. The controller performs a process for extracting the identification information of the other radio terminals from the received data stored in the RAM. The controller displays the extracted identification information of the other radio terminals on the monitor.

Abstract: In data communication utilizing amateur radio, communication via Internet can be performed. A radio terminal belonging to an internal network can communicate with a radio terminal belonging to another internal network via the Internet. Each radio terminal has a callsign, and a gateway has a global IP address and a table which associates each radio terminal with the global IP address of a corresponding gateway. When receiving from a radio terminal, information addressed to a radio terminal in another internal network, the gateway sends the received information to the Internet by addressing it to the global IP address of the gateway of the internal network to which the destination radio terminal 33 belongs with reference to the table. When receiving information from the Internet, the gateway sends the received information to a radio terminal specified by the callsign of a receiver.

Abstract: An FM modulation signal is mixed with a pair of first local oscillation signals to be converted to a pair of base band signals. The base band signals are respectively mixed a pair of second local oscillation signals. The resultant signals are added together, thereby yielding an IF signal which is in turn detected. The local oscillator generates a reference oscillation signal whose frequency corresponds to a carrier component of the IF signal and frequency-divides the reference oscillation signal, thus generating the second local oscillation signals. The frequency of the first local oscillation signal converges to the one that has a given ratio to the frequency of the reference oscillation signal.

Abstract: An FM modulation signal is mixed with a pair of first local oscillation signals to be converted to a pair of base band signals. The base band signals are respectively mixed a pair of second local oscillation signals. The resultant signals are added together, thereby yielding an IF signal which is in turn detected. The local oscillator generates a reference oscillation signal whose frequency corresponds to a carrier component of the IF signal and frequency-divides the reference oscillation signal, thus generating the second local oscillation signals. The frequency of the first local oscillation signal converges to the one that has a given ratio to the frequency of the reference oscillation signal.

Abstract: An FM modulation signal is mixed with a pair of first local oscillation signals to be converted to a pair of base band signals. The base band signals are respectively mixed a pair of second local oscillation signals. The resultant signals are added together, thereby yielding an IF signal which is in turn detected. The local oscillator generates a reference oscillation signal whose frequency corresponds to a carrier component of the IF signal and frequency-divides the reference oscillation signal, thus generating the second local oscillation signals. The frequency of the first local oscillation signal converges to the one that has a given ratio to the frequency of the reference oscillation signal.

Abstract: A tape guide member is disclosed which is prepared from a mixture of engineering plastics, carbon fibers, and an ester of a higher fatty acid, and a polyhydric alcohol. The members may be suitably used as tape guides of video tape cassettes, audio tape cassettes, and memory tape cassettes. Use of the present tape guide results in a lower degree of dropouts after repeated tape running.

Abstract: An address converter for decoding a multi-bit binary address has a binary adder to provide a logic subtraction of binary bit information introduced by a plurality of manually settable switches from a predetermined number of most significant binary bits in an address signal, an address-decode circuit for receiving an output signal from the adder and the next order of magnitude of the binary bits in the address signal and a plurality of system subunits which receive an output signal from the address-decode circuit and the remaining least significant bit information in the address signal to access the subunits according to the address signal and the switch settings in a predetermined order.